Tom Vinson, director of Federal regulatory affairs at the American Wind Energy Association, begs to differ. He points out that this is the first such project to obtain Washington's approval, and that all offshore projects further than 3 miles from the coastline require Federal approval. He says Cape Wind now has all required state, local, and Federal permits, except possibly one from the FAA, which must approve any structure higher than 200 feet.

That's not trivial. But I stand by my observation that potential is not the same as realistically developable. Every offshore project will be controversial, and I'll be very surprised if oceanic offshore wind is generating 3 percent of U.S. electricity by 2020 or 2030.